This is what David Neale writes on his fantastic site Elvis Originals, http://davidneale.eu/elvis/originals/list6.html#S1373 :
Milkcow Blues Boogie
Recorded by Elvis on Friday, 10 December 1954;
Written by: Arnold
Originally recorded by James Kokomo Arnold in 1934 (as Milk Cow Blues)
Hear Elvis's version on: The Sun Sessions CD; The Complete 50's Masters 1
For the writer of "Milk Cow Blues," some sources list "Traditional," presumably meaning they don't know, others indicate Sleepy John Estes, and still others give Kokomo Arnold himself the credit. The song of the same title by Sleepy John Estes is a completely different number, so he, at least, can be eliminated. Arnold's own original recording, made on 10 September, 1934, and released on Decca 7026 (blue label "race" series) that same year, lists Arnold himself as the sole writer.
Certainly not traditional was Elvis's breaking into the number after a few seconds to announce, "Hold it fellahs. That don't move me — let's get real, real gone for a change," before increasing the tempo, with Scotty and Bill tagging along. Anyone who thinks that Elvis copied other artists recordings in order to break into the business has clearly not listened to Elvis's early renditions. His own version of this song, for example, bears little resemblance to Kokomo Arnold's original. Rather, it seems to indicate that Elvis had listened to thousands of pieces, some of which had left traces somewhere in his memory, traces he used to create something very different.
The last sentence of this quote can be applied to Arnold as well. This afternoon I found out that some words in Milkcow Blues Boogie resemble a complete verse of the song "My Black Mama - Part 1" quite a bit. My Black Mama is a song recorded by Son House on May 28,1930 in Grafton, Wisconsin.
In Milk Cow Blues we hear:
Well, if you've seen my milk cow
Please ride her on home
I ain't had no milk or butter
Since that cow's been gone
In My Black Mama - Part 1, verse 5:
Well, you see my milk cow, tell her hurry home
I aint had no milk since that cow been gone,
If you see my milk cow, tell her hurry home,
Yeah, I aint had no milk since that cow been gone.
And also the style of the song has some similarities:
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(Around 1:51 the fifth verse begins)
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version 2, 1935:
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Lyric wise it looks like Elvis got most of his inspiration from Arnold's 1935 version. But his howls resemble more of the first. Kokomo Arnold also recorded Milk Cow Blues No. 3, 4 and 5 by the way. But I couldn't find any examples of those. Might be interesting to learn if he made some rhythmic changes in one of those versions as well. Just like Elvis did.
BIG BILL BROONZY
But it looks like Son House was not the only inspiration for Kokomo Arnold. On this site: http://www.originals.be/nl/originals/4175 I learned that Big Bill Broonzy covered Milk Cow Blues from Arnold. But looking at the recording dates on another site I found out that Big Bill Broonzy recorded his version already on March 23, 1934 in Chicago(!) That was six months before Arnold recorded his version! Broonzy's version was released on May 16, 1934. Arnold recorded his version in Chicago, Illinois, on September 10, 1934.
"Well I woke up this morning..."
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And what about this version, from 1941. It were these lyrics Elvis used as well:
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It looks lik this one was more of influence on Elvis, than Kokomo Arnold's version.
1946 - with spoken intro and a kinda dialogue...
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1948 - O those howls!
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Remarkable
The first sentence of Arnold's Milk Cow Blues No 1 (1934) is "All in good morning, I said, blues how do you do", while the first sentence of the Son House song Walking Blues (1930) is ""Good morning blues, blues how do you do". In Milk Cow Blues No 2 the opening sentence is different. More like we know it from Elvis.
Sources
http://bluesdust.freehostia.com/component/content/article/13-m/136-my-black-mama-part-1-a-2-son-house.html
http://www.originals.be/nl/originals/4175
https://www.discogs.com/Big-Bill-Milk-Cow-Blues-Bull-Cow-Blues-Part-2/release/4854408
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